Attempting to create a feat allowing a character to choose/know one additional spell from any class' spell list. It seems like it should just be a matter of adding a line in the spells section with all spell classes selected but that isn't working so I'm clearly missing a vital step. Any help would be appreciated.

Hello! Could you link your unpublished homebrew? I would be happy to take a look and see if I can better help/understand the mechanic you're implementing here. :)

Oops! Sorry...forgot to mark this as solved. Thanks for the willingness to help, though!